Reading charge transport from spin dynamics on the surface of topological insulator

Abstract

Resolving the conductance of the topological surface states (TSSs) from the bulk contribution has been a great challenge for studying the transport property of topological insulators. By developing a non-purturbative diffusion equation that describes fully the spin-charge dynamics in the strong spin-orbit coupling regime, we present a proposal to read the charge transport information of TSSs from its spin dynamics which can be isolated from the bulk contribution by time-resolved second harmonic generation pump-probe measurement. We demonstrate the qualitatively different Dyaknov-Perel spin relaxation behavior between the TSSs and the two-dimensional spin-orbit coupling electron gas. The decay time of both in-plane and out-of-plane spin polarization is naturally proved to be identical to the charge transport time. The out-of-plane spin dynamics is shown to be in the experimentally reachable regime of the femtosecond pump probe spectroscopy and thereby we suggest experiments to detect the charge transport property of the TSSs from their unique spin dynamics.

5 pages, 2 figures + Supplementary Material; Accepted by Physical Review Letters

References in corpus (16)

• First direct observation of Spin-textures in Topological Insulators : Spin-resolved ARPES as a probe of topological quantum spin Hall effect and Berry's phase
• Topological origin of subgap conductance in insulating bilayer graphene
• Two-dimensional Dirac fermions in a topological insulator: transport in the quantum limit
• An Exact SU(2) Symmetry and Persistent Spin Helix in a Spin-Orbit Coupled System
• Emergence of the persistent spin helix in semiconductor quantum wells
• Spin current and polarization in impure 2D electron systems with spin-orbit coupling
• Interplay between ferromagnetism, surface states, and quantum corrections in a magnetically doped topological insulator
• Selective probing of photo-induced charge and spin dynamics in the bulk and surface of a topological insulator
• Nonlinear optical probe of tunable surface electrons on a topological insulator
• Non-diffusive spin dynamics in a two-dimensional electron gas
• Two-dimensional universal conductance fluctuations and the electron-phonon interaction of topological surface states in Bi2Te2Se nanoribbons
• Oscillatory D'yakonov-Perel' spin dynamics in two dimensional electron gases
• Unified theory of spin-dynamics in a two dimensional electron gases with arbitrary spin-orbit coping strength at finite temperature
• Giant mesoscopic spin Hall effect on surface of topological insulator
• Femtosecond Laser-induced Crystallization of Amorphous Sb2Te3 film and Coherent Phonon Spectroscopy Characterization and Optical Injection of Electron Spins
• Diffusive-Ballistic Crossover and the Persistent Spin Helix

Cited by in corpus (17)

• Dirac Spin-Orbit Torques at the Surface of Topological Insulators
• Unraveling photoinduced spin dynamics in topological insulator Bi2Se3
• Ultrafast spin polarization control of Dirac fermions in topological insulators
• Effects of Dephasing on Spin Lifetime in Ballistic Spin-Orbit Materials
• High Surface Conductivity of Fermi Arc Electrons in Weyl semimetals
• Spin diffusion and magnetoresistance in ferromagnet/topological-insulator junctions
• Giant magnetoresistance in the junction of two ferromagnets on the surface of diffusive topological insulators
• Spin and charge transport induced by a twisted light beam on a surface of a topological insulator
• Transmission Line Model for Materials with Spin-Momentum Locking
• Spin-charge transport driven by magnetization dynamics on disordered surface of doped topological insulators
• Spin-torque resonance due to diffusive dynamics at a surface of topological insulator
• Detection of current induced spin polarization in epitaxial Bi${}_2$Te${}_3$ thin film
• Nonequilibrium topological spin textures in momentum space
• Entropy Driven Inductive Response of Topological Insulators
• Giant Spin Transport Anisotropy in Magnetic Topological Insulators
• Spin Generation Via Bulk Spin Current in Three Dimensional Topological Insulators
• Research on topological materials using ultrafast spectroscopy